72-29b-10b^2=0

Solution for 72-29b-10b^2=0 equation:

72-29b-10b^2=0

a = -10; b = -29; c = +72;
Δ = b2-4ac
Δ = -292-4·(-10)·72
Δ = 3721
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3721}=61$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-29)-61}{2*-10}=\frac{-32}{-20}
=1+3/5
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-29)+61}{2*-10}=\frac{90}{-20}
=-4+1/2
$